>From 1e6d3b2856a6ba3f38f67ab9c8286e4bf93f0968 Mon Sep 17 00:00:00 2001 From: Sinan Kaya Date: Sun, 12 Mar 2017 01:08:54 -0500 Subject: [PATCH 3/4] PCI/ASPM: save power on values during bridge init Now that we added a hook to be called from device_add, save the default values from the HW registers early in the boot for further reuse during hot device add/remove operations. Signed-off-by: Sinan Kaya --- drivers/pci/pcie/aspm.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 7312a37..7754445 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -521,8 +521,10 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) */ if (dwreg.support & upreg.support & PCIE_LINK_STATE_L0S) link->aspm_support |= ASPM_STATE_L0S; - if (dwreg.enabled & PCIE_LINK_STATE_L0S) + if (dwreg.enabled & PCIE_LINK_STATE_L0S) { link->aspm_enabled |= ASPM_STATE_L0S_UP; + link->aspm_default |= ASPM_STATE_L0S_UP; + } if (upreg.enabled & PCIE_LINK_STATE_L0S) link->aspm_enabled |= ASPM_STATE_L0S_DW; link->latency_up.l0s = calc_l0s_latency(upreg.latency_encoding_l0s); @@ -558,9 +560,6 @@ static void pcie_aspm_cap_init(struct pcie_link_state *link, int blacklist) if (link->aspm_support & ASPM_STATE_L1SS) aspm_calc_l1ss_info(link, &upreg, &dwreg); - /* Save default state */ - link->aspm_default = link->aspm_enabled; - /* Setup initial capable state. Will be updated later */ link->aspm_capable = link->aspm_support; /* @@ -860,7 +859,21 @@ int pci_aspm_init(struct pci_dev *pdev) if (!link) { ret = -ENOMEM; goto unlock; - } + + pcie_get_aspm_reg(pdev, &upreg); + if (upreg.enabled & PCIE_LINK_STATE_L0S) + link->aspm_default |= ASPM_STATE_L0S_DW; + if (upreg.enabled & PCIE_LINK_STATE_L1) + link->aspm_default |= ASPM_STATE_L1; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_1) + link->aspm_default |= ASPM_STATE_L1_1; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_ASPM_L1_2) + link->aspm_default |= ASPM_STATE_L1_2; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_1) + link->aspm_default |= ASPM_STATE_L1_1_PCIPM; + if (upreg.l1ss_ctl1 & PCI_L1SS_CTL1_PCIPM_L1_2) + link->aspm_default |= ASPM_STATE_L1_2_PCIPM; + ret = 0; unlock: mutex_unlock(&aspm_lock); -- 1.9.1